Garden hose spray guns typically attach to the ends of garden hoses using mating threads, which are fixed in position with respect to the input ends of the spray gun bodies. A common problem with this arrangement however, is that it limits the tree movement of the spray gun in the user's hand. It is, therefore, desirable to provide a spray gun that may pivot independently of the garden hose and not restrict the free movement of the user during normal cleaning or watering chores. It is contemplated that the addition of a quick coupler could provide the general affect of a swivel but such an arrangement is not designed to withstand the constant movement and pressure that it would endure during common usage. In the end, such a design will tend to leak very easily.
It is contemplated that a swivel connector could be used with a spray gun connector. However, in many prior art swivel designs, the rotor and housing rotate with respect to one another in a less than accurate fashion. Frequently, there is a fair amount of concentric play between the rotor and the housing, which is a significant contributor to leaks. In an attempt to provide a swivel that does not leak, various prior art designs increase the pressure on the O-ring seals within the swivel assembly. One problem with this design approach, however, is that the increased pressure on the O-rings also increases the torque required to rotate the swivel. This oftentimes causes premature wear on the O-rings, which can shorten the life of the swivel and cause premature leaking; the very condition the design sought to avoid. Moreover, such increased torque in prior designs can cause the user's hose to kink.
Prior swivel designs are also difficult to assemble. Conventional designs typically include an interrupting feature in the bearing raceway, such as a bearing opening that is cross-drilled into the raceway. Such a design makes it more difficult to assemble, which will cause an end user trouble when it is time to replace a tailed O-ring seal. This may happen routinely, increasing the operational costs to the user. With prior art designs, this is a fairly complicated repair in the field and may cause more problems than it resolves.
Another design shortcoming with the bearing raceways of prior swivel designs is the level of operational friction generated by the raceways during use. Conventional raceway designs are mostly circular in cross-section and sized just larger than the diameter of the bearings used therein. Accordingly, each bearing within such a raceway engages the surface of the raceway around an entire circumferential portion of the bearing. When multiplied by several bearings within a single swivel design, the amount of friction becomes significant. Moreover, such designs typically require high precision machining, which increases manufacturing costs and the potential for faulty swivel assemblies.
Standard pistol grip gun designs further suffer from restricted flow due to the types of valves used. This restriction can be acute and severely affect the amount of water available for cleaning or watering operations. Accordingly, it is desirable to create a spray gun that does not restrict the available water flow or pressure.